
What makes the Tuna Mayonnaise Spam Musubi so popular with Japanese convenience store customers?
If someone were to ask us what the most popular type of onigiri rice ball was at convenience store chain Family Mart right now, we’d probably take a guess and say, “salmon” or “tuna and mayonnaise“.
While we’d be right at any other time of year, when these usually are the top-selling flavours, it appears there’s now a new number one, as the Spam musubi has smashed the competition, selling over four million units to date since its nationwide release on 3 August.
The success of the Spam musubi (rice balls are known interchangeably as “onigiri” or “omusubi” in Japan), has been a surprise to many. However, one person not surprised by its popularity is our Japanese-language reporter, Ikuna Kamezawa, who tried a total of eight convenience-store Spam rice balls last year in Okinawa, where the tinned meat is incredibly popular.
Given its popularity in Okinawa, Family Mart has now decided to let the rest of the country get a taste of the action, this time with a new Spam musubi that’s available at all their locations across Japan…except in Okinawa.
▼ Sorry, Okinawa — this is one Spam rice ball you won’t be getting.
While Ikuna was familiar with Spam as a rice ball ingredient due to her experience in Okinawa, most of her colleagues in the office had never tried one, or even seen one, before. Our reporter Saya Togashi said she was particularly keen to get a taste of it, so she popped by her local branch of Family Mart and picked one up to find out what made them so popular.
The bright blue Spam-like packaging immediately jumped out at her, stealing her attention away from the much cheaper 100-yen (US$0.91) onigiri on the shelves. At 248 yen, the Spam Musubi was a much more expensive option, but when she returned home and got out her kitchen scales to weigh the rice ball, she found it was much heavier than most, weighing in at a hefty 180 grams (6.3 ounces).
On the packaging, Saya could see the words “Spam“, “pork & egg“, and “Tuna Mayonnaise” written on it in English, but she was still baffled as to what the combination would taste like. So she tore the package open and took a peek inside.
Cutting the musubi in half to get a good look at the cross-section, Saya could see the layers of ingredients inside. There was a thin slice of egg omelette, a generous layer of tuna mayo, and a thick slice of Spam, all sitting in the middle of a mound of rice which was wrapped in seaweed.
Saya, who grew up in northern Japan, far, far away from the southern island of Okinawa, was a little embarrassed to admit that this would be her first time tasting Spam. She’d never had it on its own, or as part of a meal, so her first introduction to the tinned meat would be inside a rice ball.
▼ Although given the shape of this rice ball, it was more like eating a rice burger.
Saya took a bite and the first thing she said was, “Oh my god, it’s salty!” She’d imagined the meat would have an oily taste like ham or bacon, but it was simple and soft, like eating a processed fish sausage.
After she got used to the texture, she was pleasantly surprised to find it had a homely flavour to it. It was like a rice ball her mum would’ve made for her when she was little, with a simple flavour that makes it easy for anyone of any age to eat.
▼ The rice was a perfect partner for the Spam, and she was impressed to see that it didn’t escape out the sides as she ate it.
It was a lot saltier than she’d expected, but it was incredibly tasty, especially with the tuna mayo, as the acidity of the mayonnaise helped to reign in some of the saltiness from the Spam. It was a good portion size too, as it filled her up nicely, and it wasn’t just her belly that was filled, but her soul too.
▼ No wonder they call this Okinawan soul food!
After trying the Spam musubi, Saya says it’s indeed worthy of the top title as a number-one bestseller, and she hopes it’ll become a permanent fixture in mainland Japan, not just at Family Mart stores but other convenience stores too.
There’s now just one question that’s left to be answered: with this pork-and-egg onigiri unavailable in Okinawa, does that mean there’ll be another job ad for a courier to fly the rice ball to the southern island chain?
Images ©SoraNews24
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[ Read in Japanese ]










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